Trailer coupling



Jan. 1, 194-6 H. c. REIMANN ETAL 2,392,063

TRAILER COUPLING Filed Nov. 18, 1944 2 Sheets-Sheet l i l 5mm. WW

1, 1946- H. c. REIMANN ETAL 2,392,063

TRAILER COUPLING Filed Nov. 18, 1944 2 Sheets-Sheet 2 32 H IIIJ ll] ATTORNEYS.

Patented Jan. 1, 1946 HowardC. Riemann, West Milwaukee, and J oel R. Tharp, West Allis, Wis., assignors to The Fulton Company, West Allis, Wis, a corporation of Wisconsin Application November 18, 1944, Serial-No.- 564,036

'7 Gla'iins.

The resent-invention relatesin general to improvelnents irt the art o'f man u'facturlng couplings for connecting trailers to propelling vehicles or the like, and relates morepartlcularly' to improvements' iii thecpnstruction and operation of trailer couplings formed"primarilybfsheet metal.-

The principal object df 'ollr i nveiitlon'is to rovideizn'p'rove'd trailer coupling which may be manufactured at moderate cost from sheet metal or the: like with the aid of punches and dies, and which is of sturdy construction and emcient. in operation;

Many diiferent types of so-ca'llecl trailer couplings for detachably' connecting trailing vehicles t'otractors, trucks and pleasure: cars, have heretofore' been proposed and" used: extensively, with varying degrees of success; and in most cases these prior devices were constructed" of cast m'etal parts except for standard springs and fasteners used: their assemblages. Perhaps one of the most successful of the'sepriortrailer couplings-is the type shown in U. S. Patent Now $250,661, granted Ju1y29; 1941, which comprises in general acoupling member or body having a spherical frontsocket and a rear shank-formed'for attachmentto atrailing vehicle, a; spherical member or ball element cooperable with'thebody socket and being attachable to the pulling vehicle; a retainer plate "co acting with the coupling body' and having a spherical zone surface cooperable with the-ball to normally retain the same-within the socket; an adjusting bclt penetrating the plateandt'he body and having an adjusting hand wheel secured to its upper headed end, a latch having'ahub surrounding the bolt and: provided' with a locking portion engageable with teeth or notches on the hand wheel to prevent loosening: of' the bolt and a spring"v embracing the bolt' and coacting: with the latch hub to constantly urge the latch" into locking position. The'previous couplings of this particular type, were* formed primarily ofmetal castings which could be :produ'c8d onl'yatconsiderable cost-by slow=foundry methods; and which frequentlycontainedihidden defectsmakingthem dangerous and unreliable-in use;. and while some attempts were heretofore made to produce the main coupling; body, ball and retainer plate of sheet metal, theseproved rather costly and rela- Another object of this invention is to" provide a strong coupling inember'or body havihg'spher-i cal socket and attaching ortions at its opposite ends,- and which is" formed: of only a few sheet metal parts rigidly united by fusion of rectal 61' welding A' further object ofthe invention is to pro'vide a durable spherical member or ball element for couplings; which may also be formed of a limited number of simple parts firmly" united by welding and pressing to produce a most efficient and an curate 'sphere'elementw-ithout heces'sitating' costly finishing;

An additional objector our invention is reprevi'de' an improved sheet metal adjusting, assemblihg'; and dismantlihgih'and wheel assemblage for trailer couplingsg whichmay be readily construct e'd o'f two simple sta'nipings: effectively united by spot welding so as to simultaneously attach: the Wheel tciits associated adjusting boltor screwi Still another obj ect= of this invention is to provide 'ai simplified retainer plate for normally'lteep'. ihgthe-coupl ing parts united and which 'iiiay also be made or a single sheet metal stamping with the aid'o'f punches and dies;

These and: other specific objectsand a'dvam 't'ages at our: nvention will be" apparent from the similar parts in the various views.

Fig; I isa top view drone of 'the improved sheet metal trailer couplings of relatively'sinall' sizeahd limited pulling capacity adapted for comparati vely light service; i

Fig; 2 is a central longitudinal s'ection' through thecoupling'assemblage of Fig. 1 out showing" the ballmemberin elevatiomf 1 Fig: 3"is"a rear end viewofthe"trailer-coupling o'f Fig's-l and 2;"

Fig. 4 is a part sectional side elevation of the ball-member 'usedin' tlfe sm'alle'r' siz'tr'ailer' couclings of Figs. 1 th s inclusive:

Fig. 5 is a top'viewof the upperslieet metal section offl'one of'the improved adjusting hand wheel's, showing" the: formation thereof Fig; 6: is a section through the upper hand wheel portion; taken along the'line- 6-6 oflFig. 5;

Fig; '7 is a top-view of a another ofour improved sheet metal trailer couplings oflarger sizeand pulling capacity especially adapted for heavier duty;

Fig. 8 is a part sectional side elevation of the heavy duty coupling of Fig. '7;

Fig. 9 is a rear end view of the trailer coupling of Figs. 7 and 8;

Fig. 10 is a part sectional side elevation of the ball member preferably employed in the-heavier duty couplings;

Fig. 11 is a. transverse section through the ball member of Fig. 10, taken along the line Fig. 12 is a part sectional side elevation of the adjusting hand wheel and bolt used on the larger size couplings; and

Fig. 13 is a view similar to Fig. 12 but showing a modified hand wheel structure.

While the invention has been shown and described herein as having been embodied in only two specific sizes of sheet metal trailer couplings of a special type especially adapted for use on automobiles and trailers therefor, it is not our desire or intent to thereby unnecessarily restrict the scope or utility of the improved features.

Referring particularly to Figs. 1, 2 and 3 of the drawings, the improved light duty sheet metal trailer coupling shown therein comprises in general a frame or body member l4 formed of a U-shaped sheet metal strap section l5 and a-cooperating sheet metal top section l6 united by a continuous weld l1, and coacting to provide a spherical socket H3 at the front and parallel attaching portions l9 at the rear of the member H; a spherical or ball member normally coacting with the socket |8 and be ng fo ed o superimposed sheet metal top, intermediate and bottom sheet metal sections 2 l, 22, 23 respectively all firmly secured to an attaching stud 24 by means of an annular weld 25 and a clamping disc 26; a sheet metal retainer plate 21 confined within and coacting with the body top section l6 and having a spherical zone portion 28 normally coacting with the socket |8 to maintain the ball therein; an assembly bolt 29 piercing the top section l6 and plate 21 and carrying an adjustable nut 30 coacting with the latter; a bolt manipulating hand wheel 3| formed of two firmly united upper and.lower sheet metalsections 32, 33 clampingly coacting with the square head 34 of the bolt 29 and provided with an an- .nular series of teeth or notches 35 in the lower section 33; a sheet metal latch 36 extending through an opening in the body section l6 and beneath the body section l6; and a helical compression spring 39 interposed between the plate 21 and the latch hub 38.

. The strap section l5 of the frame or body member I4, is formed of a single piece of sheet metal bent into U-shape with the aid of punches piece of sheet metal bent into the shape shown in Fig. 2, with the aid of punches and dies, and the front upper portion of this section I6 provides a true continuation of the spherical socket 18, while the rear portion extends downwardly and provides an inclined seat for the rear end of the retainer plate 21. The two sections |5, |6 are rigidly united by the weld I! which extends along the entire joint or surfaces of coaction of these sections, thereby providing a durable frame structure in which the pull is transmitted primaril through-the one-piece U-shaped section 5 which is prevented from spreading by the top section I5. I

The spherical ball member 20 which is attachable to the pulling or draft vehicle by means of the stud bolt 24 forming a rigid part thereof, is likewise formed primarily of sheet metal with the aid of punches and dies, and the stud bolt 24 may be provided with a nut 4| and lock Washer 42 for facilitating attachment thereof to its carrying vehicle, and with a cotter pin 43 for preventing loss of the nut and washer. The sheet metal top section 2| of the spherical member 20 is rigidly attached to the top of the stud bolt 24 by means of a heavy annular weld 25, and has a lower serrated edge the serrations of which are snugly cooperable with similar serrations formed at the upper edge of the intermediate ball section 22. The serrations of the intermed ate section 22 have a continuous ridge 44 formed thereon as shown in Fig. 4, which overlaps the edges of the serrations formed on the top section 2|; and the lower end of the section 22 is provided with an integral inner flange 45 bored to fit the bolt 24. The base section 23 is also bored to fit the bolt 24 and is l kewise stamped from ordinary sheet metal. The clamping disc 26 is originally of frustro-conical shape and is surface hardened after forming thereof.

When assembling the ball members 20, the sections 2|, 22, 23 are first loosely assembled and placed into a snug fitting form, whereupon the discs 26 are applied to the bolts 24 and base sections 23, and are subsequently distorted and pressed firmly in place so as to cause the outer and inner disc peripheries to bite into the adjacent sections 23 and bolts 24, thus firmly and permanently uniting all of the sections 2|, 22, 23 with the stud bolt 24. The distorted discs 26 assume the approximate shape shown in Fig. 4, and form grooves 46, 41 in the sections 23 and bolts 24 respectively; and the spheres formed by the cooperating sections 2|, 22 of the members 20, are adapted to snugly fit the body member sockets l8.

As previously indicated, the retainer plate 21 of the improved coupling, is also formed of a single piece of sheet metal with the aid of punches and dies, and this plate 21 besides being provided with a spherical zone portion 28 cooperating with the adjacent ball member 20, is reenforced by opposite side flanges 48 which normally coact with the adjacent nut 30 so as to prevent the latter from turning. The adjusting bolt 29 and the retaining nut 30 coacting therewith, may be of standard construction, and as shown in Figs. 1 and 2, the bolt 29 has a square head 34, although hexagonal. headed bolts may also be employed.

The bolt 29 may normally be manipulated with the aid of an improved sheet metal hand wheel 3|, the two sections 32, 33 of which are metal stampings firmly united by spot welding or otherwise. The upper section 32 of the hand wheel harem medibetweerrzthasectionsm,wsandrthecmwned bottom sorofithefformer has beeni pressedzagainst the head 34. "The notcheswSesdf theiloweflharid whe'el section 33 are formed by inden'ting ithe -metal "-near' the bottom of this sectiom-sufiicieritly to formsa square socket 52" adapted tcxsnuglyen- "gage the four fiat sides of the 'bolt headiufihus providing a sheetmetal hand-wheelwvhioh cannot -turn relative' to the attached holt zll.

If so desired, the hand wheel 3! anii i bolt fl mayhe assembled; as-in' Fig. 13 wherein the -nut m is corilind within the sheet metal wheel" and ilthe bolt 29 pierces "the -hand wheel *coacts with the threadsof' the'nuifil).

The latch 35 its integral-" 111113 3 8=mfd 10bk- I "ing projection 31, vi-s "again' 'formed o'f =assingle sheet metal stamping; whilethe' 'helical compres 'sion spi'irrg 38 which constantly urges the-memes '-'upwardly arifd the retainer plate 21 idownwar'dly against the nut a'iflpmay bebfconyeritioh'alhcomstruction and should' be stiff enough to prevent rattling. The latch 3-6 whih ex-tends "through the top section P6 of -the body member l t-is thus prevented'from*turningabout the axis='of=the bolt 29but may 'be presseddownwardly-at will so as "to "release *the loc'king projection 3 "from "the notches *35 and' to thereby permit r'ree*turn'ing ef the harfd wheel- 31 and bolt 29 for-adjustment purposes.

'Re'ferring more-particularlyto Figs. 7*to 12ini section 16' may 'al'so be'- providedwi'th -bolt holes 53 *as shown in' Fig. 7. "I'he' -ball member 20 is "constructed a manner similar to that of the nnember '20, except that a headedbolt 2'4 *is'jprowiden ins'tead' df "a -stud b01t 24. This modified metal top section 2| by a continuous annular weld 25. Theassemblyand'retaining bolt 29 of the heavy dutycoupling is provided with a hexagonal head 34' as indicated in Figs. 8 and 12, and the lower section 33' of the hand wheel 3| is pro vided with a correspondingly hexagonal socket 52' coasting with the bolt head 34. Except for increases in thickness of stock and necessary variations in dimensions, the heavy duty coupling is the same as the lighter coupling of Figs. 1 to 6 inclusive, and both types of couplings may be constructed, assembled, or dismantled in like manner, and also function the same when properly assembled and applied to vehicles.

Since the mode of construction and assembling the two types of couplings, and the method of utilizing the same, is substantially alike, it will sufiice to describe the normal use of only the light weight type of coupling shown in Figs. 1 to 3 inclusive.

When the coupling has been properly constructed and assembled, it may be readily applied to a trailer and to a pulling vehicle with the aid of bolts inserted within the openings 40 of the body member l4, and by applying the bolt 214 mftttina'zballimembeni fiitoranpropeliing vehicle .in'rnnzobtiousimanner; I'Enefhandmheelm may hennianipuiatedttoccause :the hG1U 2B'1t02m tate within the nut 30 which is held withini the retafirtenpiate 21,zsozasaoxausemisrplateitoflower toiqaermit' free :insert'ron -T0f the ballwithini ithe :socketitfl. zAfter the ball hasibeeni'rthus inserted Within'lthesocketptheexhand wheel 3| mayiibe reversely manipulated so .asftomausethe metainer plate 21 to move into operative positionsthereby zcompressingzthe -spmng 29randcausing :theilatch 26 Stotbe izurgedtupwardly'toward itheshand' wheel. whenzthe-iplate 21 ihas'zbeen :elevated sufllclently so as tolretaincthezballr-zwithin :the ssocketabutito :pemnit relatively :free universal zmovement tween thefzmem'bers 1111, 52 0 time ihani'l wheel 131 rmayzberiturned: slightlylssmas to rpermit 'theilockring zproieetion t'l to :enter lthe mearest notch T35, whereupon the -parts will be locked'rin-adiusted position rand the -couplin'g is ready tor -normal use. During normal operationiof the coupling, the :ball member may :oscillate within -:-the socket :18 of the' body :member T4, so that ve'hicles imay' be operated over -uneven ground. When 'ifibecQmesdeSirabIe to-detach theWriiiler -frem the' pulling -'-vhitle, it 1 is *oiily -neeessary to release 'the' latch 36 rand-to thereafter-manipulate the hand whet-:1 I soas' to lower the. retainer plate 21=-sdfficieiitly to permit-'witlidrawal-zo ithe betll 'from within'thesoeket. "-If theplay b' tween the ball-and socket is *too greatfithe hand wheel 3! may obviously' betumed fraction of arevolutio-n so as to eliminate suchexcessiveplay. lt will thrusbe-noted that theimproved-trailer eout pling-v'r-hi'ch isma'de primarilydhsheetmetal with the aidof'punhesand dies, will*functien' to--pro- 'vide a universal connex'ztionbetween the *pro- *pelling and"-trailing vehicles, and wilr alsvpermit ready attachmentand detachment of thetwo vehicles, From the "foregoing detailed descriptionfitwill be apparent that our present invention-provides an' improved trailer coupling" which is extremely simple, *compact -and durable in "construction, and which "may "be "readily'constructed'ab mod erate*costwiththe'aid ofpunchesand dies. The improved body member [4,. [4 may ,be sturdi-ly 'weldedtogether totprovide an "extremely strong pulltransmittingelement. iThemembenflfitP 'may hefreaiiilytattachedtoatrailin'g vehiclefarfd "either attached'to or dtached fromthe "pullin vehicle; and the improved ball member 20, 20' may be sturdily and accurately constructed from sheet metal and firmly attached to the supporting bolt 24, 24'. The improved sheet metal hand wheels 3|, 3| may also be readily constructed of two pieces of sheet metal, so as to fit either square head or hexagonal headed bolts, and are firmly applied to their carrying bolts by virtue of the improved construction of the lower sections thereof. The retainer plate 21 and the latch 36 are also readily constructable from sheet metal with the aid of punches and dies, and the entire assemblage is exceedingly strong and rigid and can stand considerable shock without becoming inoperative. The invention has proven highly satisfactory in actual use, and the improved couplings while being stronger than the prior cast metal couplingsof the same type, may be produced at comparatively low cost as compared to the cost of the prior couplings. With the aid of the present invention, the trailer couplings can obviously be produced or relatively light but .to limit this invention to the exact details of construction or to the precise mode of use; herein shown and described, for various modifications within the scope of the appended claims may occur to persons skilled in the art.

We'claim:

,1. In a tow coupling, a body member, a ball membercooperable with said body member, and a retainer plate for detachably connecting said members, said body member comprising a U- shaped strapsection providing a seating socket for said ball member, and an intervening section having a spherical zone top welded to the upper part of the socketed portion of said strap section to complete thensocket and also having an integral rear wall providing a reaction abutment for said retainer plate.

2. In a tow coupling, a body member, a sheet metal ball member cooperable with said body member, and a sheet metal retainer plate for detachably connecting said members, said body member comprising a U-shaped sheet metal strap section providing a seating socket for said ball member, and an intervening sheet metal section havinga spherical zone top welded to the upper part of the socketed portion of said strap section to complete the socket and also having an integral rear Wall providing a reaction abutment for said retainer plate.

3. In a tow coupling, a body member, a ball member cooperable with said body member, and a retainer plate for detachably connecting said members, said bodymember comprising a U- shaped strap section providing a seating socket for said ball member and having parallel spaced side portions extending rearwardly away from said socket, and an intervening section having a spherical zone top welded to the upper part of ing a U-shaped strap having a seating socket and the socketed portion of said strap section to complete the socket and also having an integral rear wall welded to said side strap portions and providing a reaction abutment for said retainer plate.

d. In a tow coupling, a body member, a sheet metal ball'member cooperable with said body member, and a sheet metal retainer plate for detachably connecting said members, said body a member comprising a U-shaped sheet metal strap integral parallel spaced side portions extending rearwardly away from the socket and an intervening section welded to the top of the socket and provided with an integral wall extending downwardly between and welded to said side portions remote from said socket, a ball member coacting with said socket, and a retainer plate confined within-said body and having a front portion coacting with said ball member and a rear end reacting against said wall.

6. In-a tow coupling,- a sheet metal body member comprising a U-shaped sheet metal strap having a seating socket and integral parallel spaced side-portions extending rearwardly away from the socket and an intervening sheet metal section welded to the. top of the socket and provided with an integral wall extending downward- 1y between and welded to said side portions remote from said socket, a sheet metal ball member coacting with said socket, and a sheet metal retainer plate confined within said body and having a front portion coacting with said ball member and a rear end reacting against said wall. I

7. In a tow coupling having coacting ball and socket members, said ball member comprising a central attaching-bolt, a sheet metal spherical zone section firmly Weldedto an end of'said bolt, another sheet metal spherical zone section coacting with said first mentioned section to complete the ball, a sheet metal base section having a bore snugly fitting said bolt and also coacting with said second spherical zone section, and a hard frustro-conical clamping disc forced into biting coaction with said base and second sections to clamp all of said sections together, the engaging ends of said spherical zone sections being serrated to provide a serrated joint extending medially around the ball.

HOWARD C. RIEMANN. JOEL R. THORP. 

